EVALUACIÓN DE LA ACTIVIDAD Y EXPRESIÓN GÉNICA DE ENZIMAS ANTIOXIDANTES (SOD, GPX, GST, GR y CAT) COMO BIOMARCADORES DE EXPOSICIÓN A FTALATOS EN CULTIVO CELULAR

Elizabeth Brassea Pérez (2023, [Tesis de doctorado])

"El plastificante bis(2-etilhexilo) ftalato (DEHP) altera el equilibrio entre la producción de especies reactivas de oxígeno y las defensas antioxidantes. A pesar de la información disponible sobre los efectos tóxicos del DEHP en organismos modelo, la respuesta celular al DEHP en especies naturalmente adaptadas para tolerar el estrés oxidativo aún no se ha explorado. Los mamíferos marinos están naturalmente adaptados para hacer frente al estrés oxidativo derivado de la isquemia/reperfusión inducida por el buceo. El objetivo de este estudio fue comparar los cambios en los indicadores de estrés oxidativo asociados al DEHP en células de músculo esquelético de humanos (Homo sapiens sapiens) y lobos marinos de California (Zalophus californianus). Se recolectaron muestras de músculo abdominal de mujeres sanas sometidas a cesárea programada, tras obtener su consentimiento informado. Las muestras de músculo de lobo marino se obtuvieron de crías encontradas recientemente muertas en la colonia de Los Islotes, Golfo de California. Las células de músculo esquelético se aislaron y cultivaron en condiciones estándar. Las células se dividieron en dos grupos. Un grupo fue expuesto a DEHP (1 mM) durante 13 días (n=25; exposición), el otro grupo se mantuvo bajo condiciones control, es decir sin DEHP añadido (n=25; control). Se midió la producción de radical superóxido (O2•-), el daño oxidativo, la actividad de enzimas antioxidantes y la expresión génica mediante métodos espectrofotométricos y RT-qPCR. En células expuestas al DEHP la producción de O2•- y la actividad de superóxido dismutasa (SOD) fueron mayores que en las células bajo condiciones control para ambas especies. La actividad de glutatión S-transferasa (GST) y los niveles de carbonilos proteicos (PC) aumentaron significativamente en las células humanas expuestas a DEHP, y no significativamente en las células de lobo marino. Por el contrario, las actividades de glutatión peroxidasa (GPx) y catalasa (CAT) aumentaron significativamente en las células de lobo marino, pero no en las de humano expuestas a DEHP. Se observó una expresión diferencial de los genes implicados en el metabolismo redox entre las células control y expuestas a DEHP y entre especies. Los patrones de expresión de 26 y 19 genes fueron significativamente diferentes en las células humanas y de lobo marino, respectivamente, después de la exposición a DEHP. En las células humanas, la expresión de la GST1 microsomal y la GST (κ, μ, θ, ω y ᴢ) fue mayor,

"The plasticizer bis (2-ethylhexyl) phthalate (DEHP) dysregulates the balance between reactive oxygen species production and antioxidant defenses. Despite the information available on DEHP’s hazardous effects in model species, the cellular response to DEHP in organisms naturally adapted to tolerate oxidative stress remains unexplored. Marine mammals are naturally adapted to cope with oxidative stress derived from diving-induced ischemia/reperfusion. The objective of this study was to compare changes in oxidative stress indicators induced by DEHP in human (Homo sapiens sapiens) and California sea lion (Zalophus californianus) skeletal muscle cells. Abdominal muscle samples were collected from healthy women undergoing planned cesarean surgery at full term after obtaining informed consent. Sea lion muscle samples were obtained from recently deceased pups at Los Islotes rookery, Gulf of California. Skeletal muscle cells were isolated and cultured under standard conditions. Cells were divided into two groups. One group was exposed to 1 mM DEHP for 13 days (n=25; treatment), and the other served as a control (n=25; no DEHP). Superoxide radical (O2•-) production, oxidative damage, antioxidant enzyme activities and gene expression were measured using spectrophotometric methods and RT-qPCR. DEHP exposure increased O2•- production and superoxide dismutase (SOD) activity in both species. While the activity of glutathione S-transferase (GST) and protein carbonyls (PC) levels significantly increased in human cells, these indicators showed a non-significant elevation in sea lion cells. In contrast, glutathione peroxidase (GPx) and catalase (CAT) activities increased significantly in sea lion but not in human cultures exposed to DEHP. Genes involved in redox metabolism showed differential expression between treatments and species. DEHP exposure led to widespread modifications in gene expression patterns, with 26 and 19 differentially expressed genes in human and sea lion cells, respectively. In human cells, DEHP increased GST1 and GST (κ, μ, θ, ω, and ᴢ), while suppressing 8-oxoguanine DNA glycosylase (OGG1), CAT, GR, and nuclear factor erythroid 2-related factor 2 (NRF2) expression, suggesting increased oxidative stress and phase two detoxification processes. In contrast, DEHP increased OGG1, NRF2, GPx2 and SOD3 expression, suggesting that DEHP activates antioxidant defenses in sea lion cells, potentially contributing to maintain redox homeostasis and avoid oxidative...

Contaminantes emergentes, enzimas antioxidantes, estrés oxidativo, mamíferos, Una Salud Antioxidant enzymes, emerging pollutants, mammals, One Health, oxidative stress BIOLOGÍA Y QUÍMICA QUÍMICA BIOQUÍMICA ENZIMOLOGIA ENZIMOLOGIA

A Computational Method for the Binding Mode Prediction of COX-1 and COX-2 Inhibitors: Analyzing the Union of Coxibs, Oxicams, Propionic and Acetic Acids

ESTEFANY BELLO VARGAS JOSE MARIO ORDOÑEZ PALACIOS (2023, [Artículo])

Among the biological targets extensively investigated to improve inflammation and chronic inflammatory conditions, cyclooxygenase enzymes (COXs) occupy a prominent position. The inhibition of these enzymes, essential for mitigating inflammatory processes, is chiefly achieved through Non-Steroidal Anti-Inflammatory Drugs (NSAIDs). In this work, we introduce a novel method—based on computational molecular docking—that could aid in the structure-based design of new compounds or the description of the anti-inflammatory activity of already-tested compounds. For this, we used eight crystal complexes (four COX-1 and COX-2 each), and each pair had a specific NSAID: Celecoxib, Meloxicam, Ibuprofen, and Indomethacin. This selection was based on the ligand selectivity towards COX-1 or COX-2 and their binding mode. An interaction profile of each NSAID was compiled to detect the residues that are key for their binding mode, highlighting the interaction made by the Me group. Furthermore, we rigorously validated our models based on structural accuracy (RMSD < 1) and (R2 > 70) using eight NSAIDs and thirteen compounds with IC50 values for each enzyme. Therefore, this model can be used for the binding mode prediction of small and structurally rigid compounds that work as COX inhibitors or the prediction of new compounds that are designed by means of a structure-based approach.

BIOLOGÍA Y QUÍMICA QUÍMICA anti-inflammatory, cyclooxygenase (COXs), molecular docking, NSAIDs, Celecoxib, Meloxicam, Ibuprofen,

Predicción de actividad antimicrobiana usando modelos de escala evolutiva a través de un flujo de trabajo en la plataforma KNIME

Prediction of antimicrobial activity using models of evolutionary scale through a workflow in the KNIME platform

Karla Lorena MartÍnez Mauricio (2023, [Tesis de maestría])

Dentro de las estrategias para combatir la resistencia antimicrobiana, se está llevando a cabo investigación para la creación de nuevos fármacos basados en péptidos antimicrobianos. En los últimos años, se han realizado esfuerzos para incorporar herramientas computacionales que ayuden a acelerar la identificación de péptidos con actividad antimicrobiana. Una de estas herramientas son los modelos QSAR basados en aprendizaje tradicional, que permiten predecir la actividad antimicrobiana en péptidos a partir de información basada en su secuencia. Un componente clave en este proceso es el tipo de características moleculares a utilizar. Recientemente, ha surgido una familia de modelos pre-entrenados llamados ESM-2, los cuales generan incrustaciones (características) que fueron aprendidas a partir de 65 millones de secuencias que abarcan diversidad evolutiva. En este trabajo de tesis, se analiza la contribución de las incrustaciones ESM-2 de diferentes dimensiones de forma individual y en conjunto en el desarrollo de modelos QSAR basados en aprendizaje tradicional para la clasificación de péptidos antimicrobianos, así como sus tipos funcionales, como antibacteriano, antifúngico y antiviral. A partir de este estudio se concluye que aumentar la capacidad de los modelos ESM-2 no implica una mejora en el rendimiento de los modelos para predecir péptidos antimicrobianos. Los modelos ESM-2 t30 y ESM-2 t33 son los más apropiados para extraer características y mejorar la exactitud en las predicciones de péptidos antimicrobianos. Además, fusionar características de diferentes incrustaciones ESM-2 es una estrategia efectiva para construir mejores modelos QSAR que el uso exclusivo de características derivadas de un modelo ESM-2 específico. Se construyeron modelos más simples con un rendimiento comparable o superior a los modelos basados en aprendizaje profundo reportados en la literatura. Para llevar a cabo este estudio se implementó un flujo de trabajo en KNIME que genera de forma automática hasta 1980 modelos de clasificación binaria basados en aprendizaje tradicional. Incorpora diversas técnicas de selección de características, algoritmos de clasificación, métricas de desempeño y una fase de limpieza de datos. Este flujo de trabajo se encuentra disponible en https://github.com/cicese-biocom/classification-QSAR-bioKom.

Molecular features play an important role in different bio-chem-informatics tasks, such as the Quantitative Structure-Activity Relationships (QSAR) modeling. Several pre-trained models have been recently created to be used in downstream tasks either by fine-tuning a specific model or by extracting features to feed traditional classifiers. In this sense, a new family of Evolutionary Scale Modeling models (termed as ESM-2 models) has been recently introduced, demonstrating outstanding results in structure protein prediction benchmarks. Herein, we are devoted to assessing the usefulness of different-dimensional embeddings derived from ESM-2 models in the prediction of antimicrobial peptides, given the great deal of attention received because of their potential to become a plausible option to mainly fight multi-drug resistant bacteria. To this end, we created a KNIME workflow to guarantee using the same modeling methodology, and consequently, carrying out fair comparisons. As a result, it can be drawn that the 640- and 1,280- dimensional embeddings are the most appropriate to be used in modeling because statistically better results were achieved from them. We also combined features from different embeddings, and we can draw that the fusion of features of different embeddings contributes to getting better models than only using a specific model ESM-2. Comparisons regarding state-of-the-art deep learning models confirm that when performing methodologically principled studies in the prediction of AMPs, non-DL based models yield comparable-to-superior results to DL-based models. The implemented KNIME workflow is availablefreely at https://github.com/cicese-biocom/classification-QSAR-bioKom. We consider that this workflow can be valuable to prevent unfair comparisons regarding new computational methods, as well as to propose new non-DL based models.

péptidos antimicrobianos, QSAR, aprendizaje automático ESM-2, KNIME antimicrobial peptides, QSAR, machine learning, ESM-2, KNIME INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ORDENADORES DISEÑO CON AYUDA DE ORDENADOR DISEÑO CON AYUDA DE ORDENADOR

Antioxidant profile of hot and sweet pepper cultivars by two extraction methods

MERCEDES GEORGINA RAMIREZ ARAGON ENRIQUE TROYO DIEGUEZ Pablo Preciado Rangel Victoria Jared Borroel García Miguel García-Carrillo JOSE LUIS GARCIA HERNANDEZ (2022, [Artículo])

"Chili peppers are among the most important vegetables in the world. The demand of this fruit reveals a noticeable rapid increasing, which importance is mainly due to its nutraceutical composition. These fruits are rich in capsaicinoids, phenolic compounds, carotenoids, and others, including vitamins. In this study, a comparative evaluation between two extraction methods of bioactive compounds of fourteen chili pepper cultivars was performed. Two extraction methods for antioxidants, the time-solvent and the ultrasound were evaluated. The design of the experiment was completely randomized with three repetitions where variables evaluated were total phenolic compounds, flavonoids content, antioxidant capacity and capsaicin. Results showed that the phenolic compounds oscillated between 48.7 - 634.1 mg GAE/100 g dry weight (DW), the flavonoids content varied from 1 - 97 mg QE/100 g DW, the antioxidant activity from 65 - 348 µmol Trolox/g DW and the capsaicin content oscillated from 0.3 - 922 mg/100 g DW. The extraction method with higher values of bioactive compounds for each of the chili pepper types was the ultrasound for all the measured variables."

Capsicum annuum, phenolics, flavonoids, capsaicin, ultrasound, antioxidant capacity CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS AGRONOMÍA PRODUCCIÓN DE CULTIVOS PRODUCCIÓN DE CULTIVOS

Hacia el desarrollo de un nuevo antiparasitario basado en células en suspensión de Carica papaya

CYNTHIA ALEJANDRA GUZMÁN MEDINA (2023, [Tesis de doctorado])

Las enfermedades parasitarias son un problema de salud pública que afectan a más de la

quinta parte de la población a nivel mundial. Además de la morbilidad que generan, sino

son tratadas y controladas de manera adecuada pueden llegar a causar la muerte.

En el mercado existen diferentes antiparasitarios comerciales, que si bien son efectivos,

presentan diferentes efectos adversos tanto para el individuo parasitado (i.e. destrucción

de la microbiota intestinal) como para el medio ambiente. Este panorama señala la

relevancia de desarrollar tratamientos antiparasitarios más amigables con el ambiente y con

menores efectos adversos que estén disponibles actualmente en el mercado. Productos

obtenidos a partir de plantas con propiedades anti-parasitarias, cultivadas in vitro en

condiciones controladas, podrían representar una alternativa realista. Entre ellas figura la

planta Carica papaya, especie de zonas tropicales y subtropicales del planeta a cuyos frutos

se les adjudica actividades antiparasitarias. Estas propiedades se atribuyen a algunos de

sus compuestos concentrados en el latex y en las semillas como la papaina, la

quimiopapaína, la lisozima, la glicil-endopeptidasa, la proteasa de cisteína y el benzil-

isotiocinato.

El objetivo del presente trabajo fue evaluar la actividad antiparasitaria in vitro e in vivo de

un conjunto de callos y líneas de células de papaya de Carica papaya contra cisticercos de

Taenia crassiceps (cestodo) y contra trofozoitos de Entamoeba histolytica (protozoario). Los

extractos acuosos obtenidos a partir de callos y células cultivados en placa o en suspensión,

respectivamente, de las diferentes líneas de papaya revelaron alta capacidad cisticida

(>98% de mortalidad) in vitro contra cisticercos de Taenia crassiceps. En la evaluación in

vivo la línea no transformada obtuvo mayor efecto cisticida a 10mg/mL reduciendo el

número de cisticercos gemantes y aumentando los cisticercos calcificados en niveles

similares a los obtenidos utilizando antiparasitarios comerciales (albendazol y niclosamida).

Las líneas transformadas y sin transformar de papaya evaluadas indujeron una alta

capacidad amebicida (97% de mortalidad) in vitro contra trofozoitos de Entamoeba

histolytica. Las diferentes líneas transformadas y sin transformar de papaya redujeron

significativamente el número de abscesos amebianos y previnieron la hepatomegalia de

manera no significativamente diferente que el anti-parasitario comercial (metronidazol).

Los resultados generados en el presente estudio señalan al extracto acuoso obtenido a

partir de cultivos en suspensión de células de papaya transformada y no transformada

indujeron alto nivel de protección in vitro e in vivo por lo tanto; este es un producto efectivo

para el tratamiento de la cisticercosis y la amebiasis.

Parasitic diseases are a public health problem that affect more than a fifth of the population

worldwide. Additionally, and along with the morbidity the produce, they can cause death if

they are not treated and controlled adequately.

There are different commercial antiparasitic on the market which, although effective,

present different adverse effects both for the individual (i.e., destruction of the intestinal

microbiota) and for the environment alike. This panorama points out the relevance of

developing more environmentally friendly antiparasitic treatments with fewer adverse effects

than the ones currently available on the market. Products obtained from plants with anti-

parasitic properties, grown in vitro under controlled conditions, could represent a realistic

alternative. Among them is the Carica papaya, a species from tropical and subtropical areas

of the planet whose fruits are believed to have antiparasitic activities. These properties are attributed to some of its compounds concentrated in the latex and seeds such as papain,

chymopapain, lysozyme, glycyl-endopeptidase, cysteine-proteinase and benzyl-

isothiocyanate.

The objective of the present work is to evaluate the in vitro and in vivo antiparasitic activity

of a set of papaya callus and cell lines from Carica papaya against cysticerci of Taenia

crassiceps (cestode) and against trophozoites of Entamoeba histolytica (protozoan). The

aqueous extracts obtained from callus and cells cultured in plates or in suspension,

respectively, of the different papaya lines revealed high cysticidal capacity (>98% mortality)

in vitro against Taenia crassiceps cysticerci. Meanwhile, in the in vivo evaluation, the non-

transformed line obtained a greater cysticidal effect at 10 mg/mL, reducing the number of

budding cysticerci and increasing calcified cysticerci at levels like those obtained using

commercial antiparasitic (albendazole and niclosamide). The papaya lines evaluated

induced a high amoebicidal capacity (97% mortality) in vitro against Entamoeba histolytica

trophozoites. The different papaya lines significantly reduced the number of amoebic

abscesses and prevented hepatomegaly in a non-significantly different manner than the

commercial anti-parasitic (metronidazole).

The results produced in this thesis indicate that the aqueous extract obtained from

suspension cultures of transformed and non-transformed papaya cells induced a high level

of protection in vitro and in vivo. Therefore, this may represent an effective product for the

treatment of cysticercosis and amoebiasis.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS Carica papaya, antiparasitario, células en suspensión, T. crassiceps, E. histolytica. Carica papaya, antiparasitic, in-suspension cells, T. crassiceps, E. histolytica.

Uso del cártamo (Carthamus tinctorius L.) como ingrediente en alimentos para juveniles del camarón Litopenaeus vannamei

ALFONSO GALICIA GONZALEZ (2009, [Tesis de doctorado])

Debido a los altos costos e incertidumbre en el abasto de la harina de pescado y pasta de soya, en los últimos años se han buscado alternativas que puedan sustituirlos sin tener un efecto negativo en el crecimiento de los camarones en el cultivo. En el presente trabajo se realizó un estudio para evaluar el valor nutricional del cártamo (Carthamus tinctorius) como fuente proteica en alimentos para juveniles de camarón blanco del Pacífico Litopenaeus vannamei. El primer capítulo comprende el estudio de la caracterización de tres productos de cártamo (HIC; Harina Integral de Cártamo, PCB; Pasta de cártamo baja en proteína y PCA; Pasta de cártamo alta en proteína) en base a su composición de nutrientes y algunos factores antinutricionales (hemaglutininas, saponinas, actividad uréasica, aflatoxinas e inhibidor de tripsina). Los productos de cártamo tuvieron un contenido de proteína entre 20.6 y 36.8%. La harina integral fue la que presentó el mayor nivel de extracto etéreo 31%, mientras que las pastas tuvieron un nivel bajo (1.8-1.0%). El contenido de fibra en el cártamo fue alto (17-23%). Los aminoácidos más abundantes en los productos de cártamo fueron el ácido aspártico y glutámico, en contraste los menos abundantes fueron lisina y metionina. Los ácidos grasos más abundantes fueron el ácido oleico, el linoleico, el palmítico y el estéarico. El contenido de calcio de los productos de cártamo varió de 0.25 a 0.42%, mientras que el contenido de fósforo varió del 0.23 a 0.25%. No se encontraron los factores antinutricionales buscados, a excepción del inhibidor de tripsina que tuvo valores bajos (7.56 UTI/mg de muestra). No se encontraron diferencias significativas en los coeficientes de utilización digestiva aparente (CUDA) de materia seca y carbohidratos de los productos de cártamo; sin embargo, sí se encontraron diferencias en los CUDA de proteína, lípidos (CUDAl) y de energía digestible (CUDAe). La actividad de las enzimas digestivas de camarones que fueron alimentados con productos de cártamo mostró un incremento en proteinasas generales y quimotripsina. La atractabilidad y el consumo de los alimentos con un 30% de inclusión de los productos de cártamo se vieron afectadas negativamente en los camarones [...]

In recent years, alternatives to fish and soybean meals in aquacultural feeds that do not have negative effects on growth of cultivated shrimp have been intensively studied in an effort to reduce the high costs and uncertainty in supplies. In this study, the nutritional value of safflower (Carthamus tinctorius) meal as a protein source in diets for juveniles Pacific whiteleg shrimp (Litopenaeus vannamei) was investigated. Initially, characterization of three safflower meals (i.e. WSM; whole safflower meal, LPSM; low-protein safflower meal and HPSM; high-protein safflower meal), focusing on chemical composition and antinutritional factors (hemaglutinine, saponine, ureasic activity, aflatoxin, and trypsin inhibitor) was conducted. Protein content ranged from 20.6 to 36.8%. Whole safflower meal contained the highest level of lipids (31%); lipids in the other safflower meals were as low as 1.0–1.8%. Fiber content was high (17–23%). The most abundant amino acids were aspartic and glutamic acids and lysine and methionine were less abundant. Oleic, linoleic, palmitic, and stearic fatty acids were present in greatest amounts. Calcium content ranged from 0.25–0.42% and phosphorus content ranged from 0.23–0.25%. Anti-nutritional factors were not found in the analyses, except for trypsin inhibitor, with values as low as 7.56 UTI mg–1 per sample. No significant differences between the apparent digestibility coefficients (ADC) for dry matter and carbohydrates in safflower meals were detected; however, protein ADC, lipid ADC, and energy ADC were different. Total proteinase and chymotrypsin increased significantly in diets where safflower meals were included. Atractability and consumption of feed with 30% safflower meals appeared to have negative effects on the juveniles [...]

atractabilidad; camarón; cártamo; Carthamus tinctorius; digestibilidad; enzimas digestivas; factores antinutricionales; Litopenaeus vannamei CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA ACUICULTURA MARINA OCEANOGRAFÍA ACUICULTURA MARINA

Molecular modeling simulation studies reveal new potential inhibitors against HPV E6 protein

Joel Ricci-Lopez (2019, [Artículo])

High-risk strains of human papillomavirus (HPV) have been identified as the etiologic agent of some anogenital tract, head, and neck cancers. Although prophylactic HPV vaccines have been approved; it is still necessary a drug-based treatment against the infection and its oncogenic effects. The E6 oncoprotein is one of the most studied therapeutic targets of HPV, it has been identified as a key factor in cell immortalization and tumor progression in HPV-positive cells. E6 can promote the degradation of p53, a tumor suppressor protein, through the interaction with the cellular ubiquitin ligase E6AP. Therefore, preventing the formation of the E6-E6AP complex is one of the main strategies to inhibit the viability and proliferation of infected cells. Herein, we propose an in silico pipeline to identify small-molecule inhibitors of the E6-E6AP interaction. Virtual screening was carried out by predicting the ADME properties of the molecules and performing ensemble-based docking simulations to E6 protein followed by binding free energy estimation through MM/PB(GB)SA methods. Finally, the top-three compounds were selected, and their stability in the E6 docked complex and their effect in the inhibition of the E6-E6AP interaction was corroborated by molecular dynamics simulation. Therefore, this pipeline and the identified molecules represent a new starting point in the development of anti-HPV drugs. © 2019 Ricci-López et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

ligand, luteolin, protein E6, protein inhibitor, ubiquitin protein ligase, ubiquitin protein ligase E6AP, unclassified drug, antivirus agent, DNA binding protein, E6 protein, Human papillomavirus type 18, oncoprotein, protein binding, protein p53, TP CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Contrabando y redes de negocios : Hispanoamérica en el comercio global, 1610-1814

Guillermina del Valle Pavón (2023, [Libro])

"Las colaboraciones que integran este libro colectivo profundizan en el análisis de algunos circuitos comerciales, que fueron claves en el juego de intercambios en Nueva España, Perú, las Filipinas, La Habana y Buenos Aires, en el arco temporal que se extiende de 1610 a 1814."

Hispanoamérica (Antiguo Régimen); Nueva España (Virreinato); Comercio; Comercio mundial; Comerciantes; Contrabando; Corrupción; Empresas; Mercantilismo; Monarquía hispánica; Mercaderes; Redes de negocios; Argentina; Estudios de caso; Siglos XVII-XIX; CIENCIAS SOCIALES HISTORIA HISTORIA POR ESPECIALIDADES HISTORIA POR ESPECIALIDADES

Effect of antimicrobial nanocomposites on Vibrio cholerae lifestyles: Pellicle biofilm, planktonic and surface-attached biofilm

ANAID MEZA VILLEZCAS (2019, [Artículo])

Vibrio cholerae is an important human pathogen causing intestinal disease with a high incidence in developing countries. V. cholerae can switch between planktonic and biofilm lifestyles. Biofilm formation is determinant for transmission, virulence and antibiotic resistance. Due to the enhanced antibiotic resistance observed by bacterial pathogens, antimicrobial nanomaterials have been used to combat infections by stopping bacterial growth and preventing biofilm formation. In this study, the effect of the nanocomposites zeolite-embedded silver (Ag), copper (Cu), or zinc (Zn) nanoparticles (NPs) was evaluated in V. cholerae planktonic cells, and in two biofilm states: pellicle biofilm (PB), formed between air-liquid interphase, and surface-attached biofilm (SB), formed at solid-liquid interfaces. Each nanocomposite type had a distinctive antimicrobial effect altering each V. cholerae lifestyles differently. The ZEO-AgNPs nanocomposite inhibited PB formation at 4 μg/ml, and prevented SB formation and eliminated planktonic cells at 8 μg/ml. In contrast, the nanocomposites ZEO-CuNPs and ZEO-ZnNPs affect V. cholerae viability but did not completely avoid bacterial growth. At transcriptional level, depending on the nanoparticles and biofilm type, nanocomposites modified the relative expression of the vpsL, rbmA and bap1, genes involved in biofilm formation. Furthermore, the relative abundance of the outer membrane proteins OmpT, OmpU, OmpA and OmpW also differs among treatments in PB and SB. This work provides a basis for further study of the nanomaterials effect at structural, genetic and proteomic levels to understand the response mechanisms of V. cholerae against metallic nanoparticles. © 2019 Meza-Villezcas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

bacterial protein, copper nanoparticle, nanocomposite, OmpT protein, OmpU protein, OmpW protein, outer membrane protein A, silver nanoparticle, unclassified drug, zeolite, zinc nanoparticle, antiinfective agent, copper, metal nanoparticle, nanocompos BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA